The present invention relates to a method of converting heat energy to mechanical energy by expanding an evaporated working fluid by an expansion means connected to an evaporator.
A great number of devices and methods for obtaining mechanical energy are known from the state of the art. For example, heat engines are known, in which a working fluid, such as water vapor is isobarically heated at a high pressure up to the boiling point in a boiler, evaporated and then superheated in a superheater. Subsequently the vapor is adiabatically expanded in a turbine doing work and condensed in a condenser giving off heat. The liquid is pressurized by a feed-water pump and fed back into the boiler. One of the drawbacks of this device is that during the expansion process in turbines high pressures of more than 15 to 200 bar have to be generated since in turbines the pressure ratio of the expansion is essential for the efficiency to be reached.
Another feature of the prior art expansion processes for converting heat energy to mechanical energy is that the condensation waste heat generated in the condensation of the working fluid is disadvantageous waste heat for the expansion process itself, which negatively affects efficiency.